When silver and gold were used as money, both their quantity and quality were open to question. The solution was _____

In general, the marginal cost curve

A) has a positive slope. B) has a negative slope. C) is horizontal. D) is vertical. E) is U-shaped.

Among the following MPC values, which one would have the highest multiplier effect?

a. 1/3 b. 2/3 c. 3/4 d. 2/5